Namespaces in Imports field not imported from:
  ‘future’ ‘iterators’ ‘readr’
  All declared Imports should be used.
Namespaces in Imports field not imported from:
  'future' 'iterators' 'readr'
  All declared Imports should be used.
Namespaces in Imports field not imported from:
  ‘future’ ‘iterators’ ‘readr’
  All declared Imports should be used.
Namespaces in Imports field not imported from:
  ‘future’ ‘iterators’ ‘readr’
  All declared Imports should be used.
Namespaces in Imports field not imported from:
  ‘future’ ‘iterators’ ‘readr’
  All declared Imports should be used.